HP ProOne 400 G1 - All-in-one - 1 x Pentium G3420T / 2.7 GHz All-in-one/ Processor Type: Pentium/ Processor Clock Speed: 2.7 GHz/ Cache Memory Installed Size: 3 MB/ Mainboard Chipset Type: Intel H81 Express/ RAM Installed Size: 4 GB/ Hard Drive Capacity: 500 GB/ Display Technology: LCD Passive Matrix/ Graphics Controller: Intel HD Graphics/ Mainboard Chipset Type: Intel H81 Express/ Processor Manufacturer: Intel/ Processor Number: G3420T/ Cache Memory Type: L3 Cache DDR3 SDRAM/ Hard Drive Spindle Speed: 7200 RPM/ Optical Storage Type: SuperMulti DVDRW/ Display Diagonal Size: 20-Inch Inch/ Display Type: LCD Display/ Data Link Protocol: Ethernet; Bluetooth; Fast Ethernet; Gigabit Ethernet/ Interfaces & Connections: USB 2.0; microphone, headphone;RJ-45/ Power Device Type: Power Supply/ Power Provided (W): 120 Watt/ Operating System: Microsoft Windows 7 Professional with Windows 8.1 Professional License/ EPEAT Level: Gold/ Energy Star Compliant: Y Manufacturer Warranty: 3 years warranty